A decorative plaster replica of an ancient Roman shield is used as a master to make light weight and strong reproductions for display. It was quickly agreed upon that the best strategy for reproduction would be a brush on mold to save on material cost and weight due to the size of the original. Rebound 40® was selected as the rubber of choice because of it's ease of use and durability in a production setting.
A decorative Roman Shield used as a model for duplication.
Hot glue is applied to the back of the shield to adhere it to the board.
Shield is pressed down on board to firmly secure it for the mold making process.
Ease Release 200 is chosen as a release for the Rebound 40 rubber that will be used in this demonstration.
A light mist of Ease Release 200 is sprayed on all surfaces for easy release of the Rebound 40 later on when the mold is finished.
Rebound 40® is measured out 1:1 by volume for first layer.
The individual components of the rubber are combined in a clean container for mixing.
Rubber is double mixed in another container to ensure a proper consistency.
First layer of Rebound 40® is brushed onto the surface of the shield.
All surfaces, including the board, are covered in a thin layer of rubber.
Silc Pig® Blue is used for the second layer to distinguish it from the first layer, this will make it easier to see areas that need to be covered.
A small amount of the Silc Pig® is dispensed into the Rebound 40® and mixed in. A double mix into a new clean container is mimicked from the first layer.
The Silc Pig® is thoroughly mixed in and the second layer is brushed over top the first layer.
Thi-Vex® is used in the third layer to thicken the rubber prior to brushing.
Thi-Vex® produces a very thick product for filling in undercuts and potential weak areas.
The thickened rubber is brushed in where the shield meets the board in order to make a tough strong edge.
A last, colored and unthickened layer of Rebound 40® is applied to the shield mold to even out all surfaces.
Rebound 40® mold is allowed to fully cure for 6 hours.
Once cured, a straight edge and utility knife are used to clean up the edges of the rubber.
Rubber flashing peels away from the board easily.
Finished Rebound 40® mold ready for the support shell.
Sonite® wax is chosen as the product to seal all surfaces prior to the application of the support shell.
All surfaces, board and rubber, are covered with Sonite Wax.
Two coats of Universal Mold Release® are applied to all surfaces to allow the cured support shell to be removed easily.
Free Form® Molding putty is chosen as a lightweight and strong mother mold material.
Free Form® is a lightweight putty that is easily dispensed by hand.
Two equal sized portions of Free Form® are dispensed for easy 1:1 mixing of the product.
Free Form® is hand mixed together.
Mixing is complete when a uniform color has been achieved.
A rolling pin, board, and wax paper will be used to roll out the putty into an even thickness.
A sheet of wax paper is placed over the board and the Free Form® putty is pressed into the wax paper.
A second layer of wax paper is placed over top the Free Form® putty and then a rolling pin smooths out the putty to the thickness of the guides on the board.
The top layer of wax paper is removed to reveal a smoothed out layer of putty that is now the desired thickness (3/8") for the support shell.
Putty, while still on wax paper is positioned over the mold, ready to be pressed into place.
Putty is placed in place and the wax paper is peeled back, leaving the putty on the mold.
This method is repeated over the entire model, covering all surfaces.
Excess putty can be trimmed with a wooden stick while it is still uncured thus eliminating any waste and making for little post-clean up work.
Wax paper can be applied to the entire mold and the putty can again be rolled thus eliminating seams and making a nice uniform mother mold.
The completed mold seam-free and ready for the next step.
Plastic cups are positioned onto the putty in order to judge leg placement for the mold support.
The impressions left from the cups mark where the legs will be placed on the mold.
More putty is mixed and each cup is filled with the mixed putty.
Cups are slightly overfilled to allow for ease of leveling out the final base.
Cups are placed back onto the mold where the impressions were made.
All four cups are now in the proper position.
A level is used to make sure that the mold will sit solid once it is cured.
All cups aligned perfectly thanks to the extra putty placed in each cup, which allowed for adjustment.
Free Form® is allowed to fully cure overnight.
In the morning, the mother mold is pried from the base board.
The Free Form® shell is removed easily from the Rebound 40® mold.
The Rebound 40® is peeled away from the master.
The Free Form® mother mold is sanded smooth and the Rebound 40® fit back in, producing a perfect mold that captures all the detail of the original.
The mold is now ready for casting Free Form® into it.
Two coats of Ease Release 200® are applied to the molding surface.
Wax paper is laid over top the rolling pin board in preparation of the Free Form®.
Free Form® Putty is dispensed in equal amounts for the first layer of the casting.
Once again, Free From® is mixed to a consistent color, placed on the board with a layer of wax paper placed over top and rolled out to a even thickness.
Top layer of wax paper is pulled off revealing an evenly rolled out layer of Free Form® ready to be applied to the molding surface.
The first layer of Free Form® is positioned and placed into the molding surface.
The putty is then pressed into all the detail on the surface of the mold.
The wax paper is removed from the Free Form®.
Additional pieces of Free Form® are applied like the first piece.
Each piece is carefully applied to the mold surface slightly overlapping a neighboring piece.
Care is given to making sure seams are tightly pressed in, when applying additional pieces adjacent to each other.
All sections of the molding surface is covered with Free Form® and all seams properly blended together.
Casting is allowed to fully cure overnight.
The next day, the Rebound 40® mold with the cured casting is removed from the mother mold.
The Rebound 40® is easily peeled back off of the casting.
The finished casting reflects perfect detail, is light weight and strong!
Post Finishing - Free Form® is easily painted with acrylic paints.